A motor vehicle body typically has a front frame, located in front of the passenger compartment, having longitudinal girders extending laterally and essentially in the vehicle longitudinal direction, which are to be structurally connected, in the area of a front wall separating the passenger compartment and the engine compartment, to a front wall crossbeam, a lateral front wall plate, and/or side sills extending essentially in the vehicle longitudinal direction.
Furthermore, a wheel housing or a wheel well is provided in this transition area. The wheel housing is typically curved inward. For the structural reinforcement of the front frame attachment, a reinforcement structure, for example, in the form of a reinforcement plate adapted to the contour of the wheel housing or the front wall plate, is often to be provided.
Thus, for example, a reinforcement plate having two sections is known from DE 100 01 102 A1, which, viewed from the passenger compartment, is situated below the floor plate and the front wall. The reinforcement plate has its first section running in a complementary manner below a transversely running front wall section in this case. A second section extends horizontally under the floor plate.
The vehicle body front structure can have a longitudinal girder on each vehicle side in this case, which forks into an inner longitudinal girder element and an outer longitudinal girder element below the floor plate. While the outer longitudinal girder element is connected to a side sill profile, the second section of the reinforcement plate extends in the transverse direction from the outer longitudinal girder element to the inner longitudinal girder element and is welded to both of them.
Further known embodiments of reinforcement structures on the front wall side provide, for example, situating a reinforcement plate on the inner side of a front wall structure facing toward the passenger compartment and connecting the lateral longitudinal girder from the opposing outer side to the front wall in the area of this material doubling. The reinforcement plate, which extends over the inwardly curved wheel housing and the front wall adjoining thereon, which runs essentially in the vehicle transverse direction, forms, together with the front wall, a material doubling to receive or fasten a front wall crossbeam and/or a front frame.
In the transition area from wheel housing to adjoining front wall, which can also be implemented integrally with the wheel housing plate, the reinforcement plate is comparatively strongly curved because of the geometrical design. Bending angles of up to 90° having bending radii in the millimeter range or in the single-digit centimeter range are certainly implemented in this case. Such bends and bending radii necessarily represent a weak point of vehicle body with regard to structural and torsional stiffness in case of load. Such reinforcement plates are accordingly to be implemented as comparatively thick-walled, or are to be manufactured from comparatively strong materials, which is at the expense of the vehicle weight and/or the production costs.
It is therefore at least one object to provide an improved reinforcement structure for the front frame attachment in the area of a motor vehicle front wall structure, which provides the vehicle body with increased structural and torsional stiffness. At least a further object is the reduction of the vehicle weight and the material expenditure, so that the fuel consumption and the production costs of the vehicle may be reduced. At least another object is to provide the motor vehicle with improved crash behavior and in particular reduce a front wall intrusion, which is oriented inward toward the passenger compartment, as a result of external force introduction.